Inflatable device and method for treating glaucoma

ABSTRACT

Catheter devices and methods for treating glaucoma and other eye diseases by expandable dilatation of Schlemm&#39;s canal and/or direct injection of medications into Schlemm&#39;s canal.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. ProvisionalApplication No. 60/131,030, filed Apr. 26, 1999.

TECHNICAL FIELD

[0002] The present invention is generally directed to a surgicaltreatment for glaucoma and other eye diseases and relates moreparticularly to an inflatable device and method for use in ophthalmicsurgery to mechanically dilate Schlemm's canal in the eye and/or instillmedications within Schlemm's canal for direct action upon the canal, thetrabecular meshwork, and adjacent tissues.

BACKGROUND OF THE INVENTION

[0003] Glaucoma is a significant public health problem, because glaucomais a major cause of blindness. The blindness that results from glaucomainvolves both central and peripheral vision and has a major impact on anindividual's ability to lead an independent life.

[0004] Glaucoma is an optic neuropathy (a disorder of the optic nerve)that usually occurs in the setting of an elevated intraocular pressure.The pressure within the eye increases and this is associated withchanges in the appearance (“cupping”) and function (“blind spots” in thevisual field) of the optic nerve. If the pressure remains high enoughfor a long enough period of time, total vision loss occurs. Highpressure develops in an eye because of an internal fluid imbalance.

[0005] The eye is a hollow structure that contains a clear fluid called“aqueous humor.” Aqueous humor is formed in the posterior chamber of theeye by the ciliary body at a rate of about 2.5 microliters per minute.The fluid, which is made at a fairly constant rate, then passes aroundthe lens, through the pupillary opening in the iris and into theanterior chamber of the eye. Once in the anterior chamber, the fluiddrains out of the eye through two different routes. In the “uveoscleral”route, the fluid percolates between muscle fibers of the ciliary body.This route accounts for ten percent of the aqueous outflow. The primarypathway for aqueous outflow is through the “canalicular” route thatinvolves the trabecular meshwork and Schlemm's canal.

[0006] The trabecular meshwork and Schlemm's canal are located at thejunction between the iris and the sclera. This junction or corner iscalled “the angle.” The trabecular meshwork is a wedge-shaped structurethat runs around the circumference of the eye. It is composed ofcollagen beams arranged in a three-dimensional sieve-like structure. Thebeams are lined with a monolayer of cells called trabecular cells. Thespaces between the collagen beams are filled with an extracellularsubstance that is produced by the trabecular cells. These cells alsoproduce enzymes that degrade the extracellular material. Schlemm's canalis adjacent to the trabecular meshwork. The outer wall of the trabecularmeshwork coincides with the inner wall of Schlemm's canal. Schlemm'scanal is a tube-like structure that runs around the circumference of thecornea. In human adults, Schlemm's canal is believed to be divided bysepta into a series of autonomous, dead-end canals.

[0007] The aqueous fluid travels through the spaces between thetrabecular beams, across the inner wall of Schlemm's canal into thecanal, through a series of collecting channels that drain from Schlemm'scanal and into the episcleral venous system. In a normal situation,aqueous production is equal to aqueous outflow and intraocular pressureremains fairly constant in the 15 to 21 mm Hg range. In glaucoma, theresistance through the canalicular outflow system is abnormally high.

[0008] In primary open angle glaucoma, which is the most common form ofglaucoma, the abnormal resistance is believed to be along the outeraspect of trabecular meshwork and the inner wall of Schlemm's canal. Itis believed that an abnormal metabolism of the trabecular cells leads toan excessive build up of extracellular materials or a build up ofabnormally “stiff” materials in this area. Primary open angle glaucomaaccounts for approximately eighty-five percent of all glaucoma. Otherforms of glaucoma (such as angle closure glaucoma and secondaryglaucomas) also involve decreased outflow through the canalicularpathway but the increased resistance is from other causes such asmechanical blockage, inflammatory debris, cellular blockage, etc.

[0009] With the increased resistance, the aqueous fluid builds upbecause it cannot exit fast enough. As the fluid builds up, theintraocular pressure (IOP) within the eye increases. The increased IOPmay compromise the vascular supply to the optic nerve that carriesvision from the eye to the brain. Some optic nerves seem moresusceptible to IOP than other eyes. While research is investigating waysto protect the nerve from an elevated pressure, the only therapeuticapproach currently available in glaucoma is to reduce the intraocularpressure.

[0010] The clinical treatment of glaucoma is approached in a step-wisefashion. Medication often is the first treatment option. Administeredeither topically or orally, these medications work to either reduceaqueous production or they act to increase outflow. Currently availablemedications have many serious side effects including: congestive heartfailure, respiratory distress, hypertension, depression, renal stones,aplastic anemia, sexual dysfunction and death. Compliance withmedication is a major problem, with estimates that over half of glaucomapatients do not follow their correct dosing schedules.

[0011] When medication fails to adequately reduce the pressure, lasertrabeculoplasty often is performed. In laser trabeculoplasty, thermalenergy from a laser is applied to a number of noncontiguous spots in thetrabecular meshwork. It is believed that the laser energy stimulates themetabolism of the trabecular cells in some way, and changes theextracellular material in the trabecular meshwork. In approximatelyeighty percent of patients, aqueous outflow is enhanced and IOPdecreases. However, the effect often is not long lasting and fiftypercent of patients develop an elevated pressure within five years. Thelaser surgery is not usually repeatable. In addition, lasertrabeculoplasty is not an effective treatment for primary open angleglaucoma in patients less than fifty years of age, nor is it effectivefor angle closure glaucoma and many secondary glaucomas.

[0012] If laser trabeculoplasty does not reduce the pressure enough,then filtering surgery is performed. With filtering surgery, a hole ismade in the sclera and angle region. This hole allows the aqueous fluidto leave the eye through an alternate route.

[0013] The most commonly performed filtering procedure is atrabeculectomy. In a trabeculectomy, a posterior incision is made in theconjunctiva, the transparent tissue that covers the sclera. Theconjunctiva is rolled forward, exposing the sclera at the limbus. Apartial thickness scleral flap is made and dissected half-thickness intothe cornea. The anterior chamber is entered beneath the scleral flap anda section of deep sclera and trabecular meshwork is excised. The scleralflap is loosely sewn back into place. The conjunctival incision istightly closed. Post-operatively, the aqueous fluid passes through thehole, beneath the scleral flap and collects in an elevated space beneaththe conjunctiva. The fluid then is either absorbed through blood vesselsin the conjunctiva or traverses across the conjunctiva into the tearfilm.

[0014] Trabeculectomy is associated with many problems. Fibroblasts thatare present in the episclera proliferate and migrate and can scar downthe scleral flap. Failure from scarring may occur, particularly inchildren and young adults. Of eyes that have an initially successfultrabeculectomy, eighty percent will fail from scarring within three tofive years after surgery. To minimize fibrosis, surgeons now areapplying antifibrotic agents such as mitomycin C (MMC) and5-fluorouracil (5-FU) to the scleral flap at the time of surgery. Theuse of these agents has increased the success rate of trabeculectomy butalso has increased the prevalence of hypotony. Hypotony is a problemthat develops when aqueous flows out of the eye too fast. The eyepressure drops too low (usually less than 6.0 mmHg); the structure ofthe eye collapses and vision decreases.

[0015] An alternative surgical method for glaucoma management can bedirected more specifally at Schlemm's canal. U.S. Pat. No. 5,360,399teaches the placement of part of a plastic or steel tube into Schlemm'scanal with injection of a viscous material through holes in the tube tohydraulically hydrodissect the trabecular meshwork. However, the '399device provides little or no option for the distance of thehydrodissection within the length of Schlemm's canal, nor suggests ameans for dilating the canal to facilitate the natural drainagetherefrom.

[0016] A need exists, then, for a system that would allow for precisedilation and expansion of Schlemm's canal along any portion thereof. Aneed exists for the selective, direct delivery of therapeutic agentsinto Schlemm's canal that provides more effective control of glaucomawith fewer systemic complications than with existing medication deliveryalternatives. In addition, a more physiologic system is needed toenhance the drainage of aqueous fluid into Schlemm's canal from theanterior chamber angle. Enhancing aqueous flow directly into Schlemm'scanal would minimize scarring since the angle region is populated with asingle line of nonproliferating trabecular cells. Enhancing aqueous flowdirectly into Schlemm's canal and naturally therefrom into thecollecting channels would minimize hypotony since the canal is part ofthe normal outflow system and is biologically engineered to handle thenormal volume of aqueous humor. Enhancing aqueous flow directly intoSchlemm's canal would eliminate complications such as endophthalmitis,hypotony, and leaks.

SUMMARY OF THE INVENTION

[0017] The present invention is directed to a novel inflatable catheterdevice and an associated method for the surgical correction of glaucomain which the inventive device is placed within Schlemm's canal and theinflatable element of the device is expanded to temporarily stretch andexpand the lumen of the canal. At that point, the inflatable element maybe used to temporarily occlude outflow through the canal, whilephysiologic material is injected through another lumen of the device,thereby distending the canal and expanding areas of stenosis within thecanal. The inflated element may be decompressed and removed after thedesired expansion is achieved, or the device may be extracted with theinflatable component expanded, to further mechanically dilate thepassageway within Schlemm's canal.

[0018] The present invention may also be employed to inject variousmedications directly within Schlemm's canal. Such medications mayinclude, but are not limited to, antifibrotics, antibiotics, and othermedications which may have direct effects within the internal structuresof Schlemm's canal, the trabecular meshwork, and other tissues of theeye. The present invention may also be employed to deploy various stentsor shunts directly within Schlemm's canal to help maintain patencywithin the canal following removal of the inflatable device.

[0019] The inventive device and method described herein thereforefacilitates the normal physiologic pathway for drainage of aqueous humorfrom the anterior chamber to Schlemm's canal and exiting to thecollecting channels, rather than shunting to the sclera or anotheranatomic site as is done in most prior art devices. In addition, thepresent invention provides a mechanism for the delivery of devices ormedications directly into Schlemm's canal and the adjacent ophthalmicanatomy.

BRIEF DESCRIPTION OF THE DRAWINGS

[0020]FIG. 1 is an illustration showing an overall view of oneembodiment of the present invention, in which the inventive device iscomprised of a dual, concentric lumen catheter with an outer lumenterminating in an inflatable sleeve, and an inner lumen which protrudesdistal to the inflatable sleeve and terminates in an open tip. FIG. 1further shows a guidewire which extends throughout the length of saidcatheter.

[0021]FIG. 2 is an illustration showing a cross sectional view at pointA-A′ as shown on FIG. 1 and detailing the concentric nature of the twolumens within this embodiment of the present invention.

[0022]FIG. 3 is an illustration showing a detail of the distal portionof one embodiment of the present invention in which the inventivecatheter is configured with the inflatable sleeve operated by theexternal lumen, and with the internal lumen protruding distally to theinflatable sleeve and containing a plurality of fenestrations beforeterminating in a blunted tip.

[0023]FIG. 4 is an illustration showing another possible embodiment ofthe inventive catheter in which the inflatable sleeve is operated by theinternal lumen, and with the external lumen extending to the origin ofthe inflatable sleeve and containing a plurality of fenestrations.

[0024]FIG. 5 is an illustration showing the relevant anatomic details ofthe human eye.

[0025]FIG. 6 is an illustration showing the anatomic relationships ofthe surgical placement of an exemplary embodiment of the presentinvention within Schlemm's canal.

[0026]FIG. 7 is a schematic illustration showing the effects onSchlemm's canal (exaggerated for purposes of this illustration) ofinjection of a medicament by one embodiment of the inventive catheter.

[0027]FIG. 8 is a schematic illustration showing the effects onSchlemm's canal (exaggerated for purposes of this illustration) ofinjection of a medicament by one embodiment of the inventive catheter.

DETAILED DESCRIPTION OF THE PRESENT INVENTION

[0028] The present invention provides catheter devices for thedilatation of Schlemm's canal of the eye by mechanically distending aportion of the canal when inflated. The inflatable catheter devices mayalso be used to provide a conduit capable of delivering therapeuticand/or expansive medicaments injected therethrough into Schlemm's canal.The inflatable catheter devices may also be used to provide a deliverymechanism for stents, shunts and the like into Schlemm's canal tomaintain patency within the canal to facilitate the natural drainage ofaqueous humor. Furthermore, optical fibers, cameras, temperaturesensors, pressure sensors, and any other probe or suitable useful devicecan be delivered to within Schlemm's canal by the present invention.

[0029] The invention provides a catheter device comprising a proximalportion manually controllable by a user, and a distal portion shaped andsized for circumferential insertion into a portion of Schlemm's canal.The device further comprises an inflation supply lumen extending fromthe proximal portion to the distal portion. The distal portion of theinflation supply lumen can be constructed of a resilient, expandablematerial for radially dilating a portion of Schlemm's canal wheninflated. Inflation can be achieved by gas or liquid injection into theproximal portion of the inflation supply lumen, and can be carefullymonitored for volume and pressure so as to accurately expand the distallumen of the catheter device to the desired amount, Therefore, thedistal portion of the inflationary lumen can move between a firstinsertion position and a second inflation position when inflated via theproximal portion.

[0030] It has not been heretofore determined that Schlemm's canal ispatent throughout its circumference in normal individuals, as opposed tobeing divided by septa into multiple dead end canals. The inventionutilizes this new knowledge to access Schlemm's canal and to create andmaintain patency within the canal with the present devices.

[0031] The proximal portion of the catheter device is designed toreceive a connector for attachment of an inflation means, such as aninjection syringe or pump. The device can also comprise a guiding lumenextending from the proximal portion to the distal portion, wherein theguiding lumen contains a steerable guidewire for directing the catheterdevice into a desired length of Schlemm's canal.

[0032] In some embodiments, the catheter device can provide medicinalcompositions therethrough for deposit into Schlemm's canal. This can beachieved by utilizing a single lumen with one or more openings orfenestrations in the distal portion thereof. In some cases, the deliveryof a medicament may itself be an inert material, such as a gel, toexpand and dilate the canal sufficiently, thereby providing atherapeutic effect. Alternatively, the catheter device can have aseparate medicament delivery lumen and an inflation lumen, as describedabove. In certain embodiments, the inflation lumen is concentricallylocated at a site along the distal portion to provide occlusion ofSchlemm's canal either distally or proximally to the material injected.

[0033] The present invention is directed to devices and surgical methodsfor dilating Schlemm's canal and/or for delivering topically activemedications directly into Schlemm's canal utilizing an inflatable devicethat is surgically inserted within at least a portion of Schlemm'scanal. The portion of the device extending circumferentially intoSchlemm's canal may be fashioned from a flexible, biologically inertmaterial. The distal portion of the catheter device has a diameterapproximately equal to that of Schlemm's canal of a human eye. Theexternal diameter of the distal portion can be between about 0.1 and 0.5mm, or preferably about 0.3 mm. The length of the distal portion can bebetween about 1.0 and 20 mm, or preferably about 10 mm. The distalportion of the catheter device can have a pre-formed curve having aradius approximately equal to that of Schlemm's canal. The radius of thedistal portion can be between about 3 and 10 mm, or preferably about 6mm.

[0034] One embodiment of the present invention is illustrated in FIG. 1,in which the shunt device 100 is shown in a side view. The shunt device100 is comprised of two portions, a proximal portion 30 which joins oneor more distal portions 40. The proximal portion 30 is tubular,containing one or more lumens in either a concentric or parallelinternal configuration. In the exemplary embodiment of the presentinvention, the proximal portion 30 is constructed of a biologicallyinert, flexible material such as silicone or similar polymers. Alternatematerials might include, but are not limited to, thin-walled Teflon,polypropylene, or other polymers or plastics.

[0035] At its proximal end, the proximal portion 30 is attached to aconnector 25 which provides fluid communication between one or morelumens within the proximal portion 30 and standard connectors formedical syringe attachment. In the exemplary embodiment of the presentinvention, the connector provides such communication with separatesubconnectors 10 and 20. Subconnector 10 terminally connects to syringeattachment 5, which provides a connection for a syringe [not shown] usedto inject materials into one or more communicating lumens within theproximal portion 30. Subconnector 20 terminally connects to syringeattachment 15, which provides a connection for a syringe [not shown]used to inject materials into one or more communicating lumens withinthe proximal portion 30. Subconnector 20 may also allow passagetherethrough for a guidewire 71 with a blunted tip 72.

[0036] The proximal portion 30 of the catheter connects with the distalportion 40. The lumen(s) of the proximal portion 30 each connect with acorresponding lumen within the distal portion 40. The distal portion 40is sized and shaped to be received within Schlemm's canal in the eye. Inan alternate embodiment, the distal portion 40 may be a continuous,tapering extension of the proximal portion 30. The distal portion 40terminates in a tip 70 which may be tapered and/or blunted, and may beopen or closed. In the embodiment shown in FIG. 1, the distal tip of theguidewire 72 extends slightly beyond the tip 70 of the distal portion 40of the device. In the embodiment shown in FIG. 1, the distal portion hasa concentric inflatable sleeve 50. In an alternate embodiment, distal tothe inflatable sleeve 50, the distal portion 40 may continue as afenestrated catheter 60, containing one or more fenestrations 65.

[0037]FIG. 2 shows a cross section at point A-A′ through the embodimentof the present invention as indicated in FIG. 1. In this embodiment, aconcentric, dual lumen catheter is provided, with an outer tube 44 andan inner tube 48. An outer tube lumen 45 is defined between the walls ofthe outer tube 44 and the inner tube 48. An inner tube lumen 49 ispresent within the inner tube 48.

[0038] A longitudinal cross-section detailing the terminal aspect of thedistal portion 40 in this embodiment of the present invention is shownin FIG. 3. In this embodiment, the outer tube 44 is continuous with theinflatable sleeve 50, and the outer tube 44 terminates in a sealed end55 at the distal end of the inflatable sleeve 50. The inner tube 48extends through the center of the inflatable sleeve 50, and continuesdistal to the inflatable sleeve 50 as the fenestrated catheter 60. Inthe present embodiment, the fenestrated catheter 60 contains a pluralityof fenestrations. 65, and terminates in a blunted, sealed distalcatheter tip 70.

[0039] In an alternate embodiment of the present invention, as shown inFIG. 4, the inflatable sleeve 50 is continuous as a terminal extensionof the inner tube 48, and the device terminates in a blunted distalcatheter tip 70 just distal to the inflatable sleeve 50. In thisembodiment of the present invention, the outer tube 44 is continuouswith the fenestrated catheter 60 terminally, such that the fenestrations65 communicate with the outer lumen 45. In this embodiment, theinflatable sleeve 50 is controlled through the inner lumen 49, which isin continuous communication with the lumen of the inflatable sleeve 50.Any materials intended to be injected into Schlemm's canal areintroduced through the outer lumen 45, and pass through thefenestrations 65 into Schlemm's canal proximal to the inflatable sleeve50.

[0040] The surgical anatomy relevant to the present invention isillustrated in FIG. 5. Generally, FIG. 5 shows Schlemm's canal 110 andthe pupil 120, with the anatomic relationship of those structures to theanterior chamber 135, the iris 140, cornea 145, trabecular meshwork 150,and lens 170.

[0041] The surgical placement and functionality of the present inventionis shown from a frontal perspective in FIGS. 6-8. FIG. 6 shows the useof an embodiment like that shown in FIG. 3, in which the inflatablesleeve 50 is proximal to the fenestrated catheter 60. The distal portion40 of the device is threaded into Schlemm's canal 110 through a surgicalincision 105, such that the inflatable sleeve 50 is entirely receivedinto the canal 110.

[0042] The guidewire 71 may be used during surgical placement of thedevice to afford temporary rigidity to the device to facilitate itsplacement. Once placement is achieved, the guidewire 71 may bewithdrawn, leaving the device 100 in the desired anatomic position.

[0043] Once the distal portion 40 of the catheter is satisfactorilyplaced within Schlemm's canal 110, the inflatable sleeve 50 is inflatedby an injection of liquid material or air through the outer lumen 45 ofthe catheter. The inflation of the inflatable sleeve 50 serves to sealSchlemm's canal 110. Subsequent injection of a desired material throughthe inner lumen 49 of the catheter is expressed through the fenestratedcatheter 60, causing local expansion of Schlemm's canal 110 distal tothe inflatable sleeve 50.

[0044]FIG. 8 shows the functionality of an embodiment like that shownpreviously in FIG. 4, in which the inflatable sleeve 50 is locatedterminally, and the fenestrations 65 are in the wall of the outer tube44 towards the catheter tip. When the inflatable sleeve 50 is inflatedby injection into the inner tube 48, Schlemm's canal 110 is effectivelysealed distal to the inflated sleeve 50. Subsequent injection of adesired material through the outer lumen 45 of the catheter is expressedthrough the fenestrated catheter 60, causing local expansion ofSchlemm's canal 110 proximal to the inflatable sleeve 50.

[0045] The surgical procedure necessary to insert the device requires anapproach through a fornix-based conjunctival flap. A partial thicknessscleral flap is then created and dissected half-thickness into clearcornea. A radial incision is made at the limbus beneath the scleral flapand deepened until Schlemm's canal is entered posteriorly. The anteriorchamber may be deepened with injection of a viscoelastic and a mioticagent. The distal portion of the catheter device is grasped and threadedinto Schlemm's canal. At the desired position, the catheter device isinflated to expand Schlemm's canal. The device is then deflated andwithdrawn. The scleral flap and conjunctival wound are closed in aconventional manner.

[0046] While the above-described embodiments are exemplary, theinvention contemplates a wide variety of shapes and configurations ofthe catheter to provide fluid communication between the anterior chamberand Schlemm's canal. The above-described embodiments are therefore notintended to be limiting to the scope of the claims and equivalentsthereof.

What is claimed is:
 1. A catheter device comprising a proximal portionmanually controllable by a user, a distal portion sized and shaped forcircumferential insertion into a portion of Schlemm's canal, and aninflation supply lumen extending from the proximal portion to the distalportion, wherein the distal portion of the inflationary lumen isexpandable and moves between a first Schlemm's canal insertion positionand a second Schlemm's canal inflation position when inflated.
 2. Thecatheter device of claim 1, further comprising a guiding lumen extendingfrom the proximal portion to the distal portion, wherein the guidinglumen contains a steerable guidewire for directing the catheter deviceinto a desired length of Schlemm's canal.
 3. The catheter device ofclaim 1, further comprising a medicament delivery lumen extending fromthe proximal portion to the distal portion, wherein the medicamentdelivery lumen has at least one fenestration therein on the distalportion for the delivery of medicaments into Schlemm's canal.
 4. Thecatheter device of claim 1, wherein the distal portion has a diameter ofabout 0.1 to 0.5 mm.
 5. The catheter device of claim 1, wherein thedistal portion has a diameter of about 0.3 mm.
 6. The catheter device ofclaim 1, wherein the distal portion has a length of about 1.0 to 20.0mm.
 7. The catheter device of claim 1, wherein the distal portion has apre-formed curvature having a radius which approximates the radius ofSchlemm's canal of a human eye.
 8. The catheter device of claim 1,wherein the distal portion has a pre-formed curvature having a radius ofbetween about 3 mm and 10 mm.
 9. The catheter device of claim 1, whereinthe distal portion has a pre-formed curvature having a radius of about 6mm.
 10. A catheter device comprising a proximal portion manuallycontrollable by a user, a distal portion sized and shaped forcircumferential insertion into a portion of Schlemm's canal, and amedicament delivery lumen extending from the proximal portion to thedistal portion, wherein the medicament delivery lumen has at least onefenestration therein on the distal portion for the delivery ofmedicaments into Schlemm's canal.
 11. The catheter device of claim 10,further comprising a guiding lumen extending from the proximal portionto the distal portion, wherein the guiding lumen contains a steerableguidewire for directing the catheter device into a desired length ofSchlemm's canal.
 12. The catheter device of claim 10, further comprisingan inflation supply lumen extending from the proximal portion to thedistal portion, wherein the distal portion of the inflation supply lumenis expandable and moves between a first insertion position and a secondinflation position when inflated.
 13. The catheter device of claim 10,wherein the distal portion has a diameter of about 0.1 to 0.5 mm. 14.The catheter device of claim 10, wherein the distal portion has adiameter of about 0.3 mm.
 15. The catheter device of claim 10, whereinthe distal portion has a length of about 1.0 to 20.0 mm.
 16. Thecatheter device of claim 10, wherein the distal portion has a pre-formedcurvature having a radius which approximates the radius of Schlemm'scanal of a human eye.
 17. The catheter device of claim 10, wherein thedistal portion has a pre-formed curvature having a radius of betweenabout 3 mm and 10 mm.
 18. The catheter device of claim 10, wherein thedistal portion has a pre-formed curvature having a radius of about 6 mm.19. A method for the surgical treatment of glaucoma and other diseases,comprising inserting the catheter device of claim 1 into Schlemm's canaland expanding the canal by inflating the distal portion of the inflationlumen.
 20. A method for the surgical treatment of glaucoma and otherdiseases, comprising inserting the catheter device of claim 10 intoSchlemm's canal and delivering a medicament into the canal through theat least one fenestration in the distal portion of the medicamentdelivery lumen.